Cooper Pairs with Broken Time-Reversal, Parity, and Spin-Rotational Symmetries in Singlet Type-II Superconductors

TL;DR

This paper demonstrates that in singlet type-II superconductors, the vortex phase can become unstable, leading to a chiral triplet component that breaks fundamental symmetries, influenced by magnetic fields.

Contribution

It reveals the emergence of a chiral triplet component in singlet superconductors' vortex phase, breaking key symmetries and tunable by magnetic field parameters.

Findings

Chiral triplet component p_x + i p_y appears in vortex phase.

Symmetry breaking effects are tunable by magnetic field.

Potential relevance to organic and high-temperature superconductors.

Abstract

We show that singlet superconductivity in the Abrikosov vortex phase is absolutely unstable with respect to the appearance of a chiral triplet component of a superconducting order parameter. This chiral component, p_x + i p_y, breaks time-reversal, parity, and spin rotational symmetries of the internal order parameter, responsible for a relative motion of two electrons in the Cooper pair. We demonstrate that the symmetry breaking Pauli paramagnetic effects can be tuned by a magnetic field strength and direction and can be made of the order of unity in organic and high-temperature layered superconductors.